Nature can be really quiet
or really loud!
It can even be musical!
We hear sound almost everywhere on Earth.
But what about sounds from space?
Despite what you might hear
in science fiction movies,
you can’t hear any sound in space.
But what if we found
a way to listen to the stars,
especially our Sun?
Even though we can’t hear it,
since sound doesn't travel
through the vacuum of space,
the Sun is incredibly loud.
The immense power emanating from its core
produces sonic waves that travel
and bounce around inside it.
Scientists aren’t exactly sure
how loud the Sun is,
but they estimate that there would be
at least 200 watts of sound power
for every square meter (1.2 square yards).
This would be equivalent to 329 decibels,
which is so loud that it would kill you.
Think of it being like an opera singer
shattering a glass,
but in this case, you’re the glass!
Our atmosphere here on Earth
provides a medium
for sound waves to be heard.
If a crow caws or a cat meows,
these sound waves produce vibrations
in the air molecules around us,
forming frequencies
that vibrate in our eardrums.
Even though space lacks an atmosphere
to transmit sound,
there are still particles
within the plasma of space
that can be affected by sound.
These ripples of energy are known as
Like sound, they are pressure waves,
but they’re also magnetic.
They're also very small and quiet,
around -100 decibels.
To put this into perspective,
a normal conversation is about 60 decibels.
So, we would need eardrums
the size of Earth to hear these waves!
Okay, so maybe having giant eardrums
isn’t the best way to listen to the Sun.
So how else could we hear it?
Immense clouds of hot gas
rising from inside the Sun,
and traveling at speeds over
produce ripples on the Sun's surface.
And if you've ever passed gas yourself,
you know that other people can hear it!
So you won't be surprised that
all that gas makes the Sun noisy too.
But since we can't hear it,
how can we measure it?
The sonic ripples on the Sun's surface
cause changes in the frequency of light,
giving scientists an accurate picture
of what is going on within the Sun.
Scientists can measure these light frequencies
and translate them into sound waves
This process of turning information
into sound is called
Just as an ambulance’s siren
changes pitch as it passes by us,
the frequencies of light
rippling across the Sun change color,
based on the direction
and speed they’re moving at.
For instance, if the Sun’s ripples
move away from us,
they stretch out and give off a reddish hue.
If they move toward us,
they become bunched up and bluish in color.
With so much movement and activity
on the surface of the Sun,
it vibrates at many different frequencies.
Using a computer,
scientists can translate the motion of
the Sun’s light waves into sound waves,
which are then sped up
so that humans can hear them.
This produces a sound similar to church bells
hitting several notes simultaneously.
As frequencies overlap and mush together,
they create rhythmic bass thumps
over a constant background hum.
It's kind of like a heartbeat near a refrigerator.
So what if we could actually hear the Sun
with our own ears?
Hypothetically,
if space had an atmosphere like ours,
how loud would the Sun be here on Earth?
Due to the inverse square law,
the Sun’s sound would travel
outward in all directions,
meaning that the surface area
of the Sun’s sound
would get larger and larger
as it emanates outward.
But the number of watts per square meter
when the sound reaches Earth
would be reduced to just
This is the equivalent of 90 decibels,
or the sound of a motorcycle engine
right by your face.
It would feel like being at
a loud rock concert,
all the time!
You’d probably want to invest
in some good earbuds.
Luckily, we are over
and the sound it produces
dissipates in space over such a great distance.
Frankly, I’d be more worried
about having to put up with the sound
of a swarm of giant mosquitoes,
but that's a story for another What If.